This sweeping English drama, based on the book by Ian McEwan, follows the lives of young lovers Cecilia Tallis (Keira Knightley) and Robbie Turner (James McAvoy). When the couple are torn apart by a lie constructed by Cecilia's jealous younger sister, Briony (Saoirse Ronan), all three of them must deal with the consequences. Robbie is the hardest hit, since Briony's deception results in his imprisonment, but hope for Cecilia and her beau increases when their paths cross during World War II.